STM32 硬件CRC的使用

/* Define to prevent recursive inclusion -------------------------------------*/
#ifndef __crc_lib_H
#define __crc_lib_H
#ifdef __cplusplus
 extern "C" {
#endif

/* Includes ------------------------------------------------------------------*/
 

/* USER CODE BEGIN Includes */

/* USER CODE END Includes */


/* USER CODE BEGIN Private defines */

/* USER CODE END Private defines */
void GHShell_CRC_Init(unsigned char crc_type)
;

unsigned short GHShell_CRC_Calculate(unsigned int pBuffer[], unsigned int BufferLength)
;      


/* USER CODE BEGIN Prototypes */
#define CRC16_MODBUS  0
#define CRC16_X25     1

/* USER CODE END Prototypes */

#ifdef __cplusplus
}
#endif
#endif /*__ crc_H */

/* Includes ------------------------------------------------------------------*/
#include "crc_lib.h"

/* USER CODE BEGIN 0 */
#include "stm32g0xx_hal.h" 
/* USER CODE END 0 */

static CRC_HandleTypeDef hcrc;
static unsigned char CRCType;

static void CRC_Swap(uint8_t *pa, uint8_t *pb);

typedef struct
{
    uint8_t   lsb8;    
    uint8_t   msb8;
    
} Crc_data;

typedef union 
{
  uint16_t    reg;
  Crc_data    val;
    
}Crc_ElementType;


/****************** Exported function ***********************/


 
/* CRC init function */
void GHShell_CRC_Init(unsigned char crc_type)
{

  hcrc.Instance = CRC;
  hcrc.Init.DefaultPolynomialUse = DEFAULT_POLYNOMIAL_DISABLE;
  hcrc.Init.DefaultInitValueUse = DEFAULT_INIT_VALUE_DISABLE;
  if(crc_type){
     hcrc.Init.GeneratingPolynomial = 4129;
/*这个值对应多项式,多项式用2的N次方加起来后就是这个值。
  设置不同的值就是不同的CRC校验多项式，STM32F4的硬件CRC只支持以太网的CRC校验*/

  }
  else{
    hcrc.Init.GeneratingPolynomial = 32773;
  }
  CRCType =crc_type;
  
  hcrc.Init.CRCLength = CRC_POLYLENGTH_16B;
  hcrc.Init.InitValue = 0xFFFF;
  hcrc.Init.InputDataInversionMode = CRC_INPUTDATA_INVERSION_BYTE;
  hcrc.Init.OutputDataInversionMode = CRC_OUTPUTDATA_INVERSION_ENABLE;
  hcrc.InputDataFormat = CRC_INPUTDATA_FORMAT_BYTES;
  if (HAL_CRC_Init(&hcrc) != HAL_OK)
  {
//    Error_Handler();
  }

}

unsigned short GHShell_CRC_Calculate(uint32_t pBuffer[], uint32_t BufferLength)
{
    Crc_ElementType Crc16;
    
    Crc16.reg =HAL_CRC_Calculate(&hcrc, pBuffer,BufferLength);
    CRC_Swap(&Crc16.val.lsb8,&Crc16.val.msb8); 
    
    if(CRCType == CRC16_X25){ 
        Crc16.reg ^=0xFFFF;
    }
     
    return (Crc16.reg);     
          
}


/******************** private function *********************/


static void CRC_Swap(uint8_t *pa, uint8_t *pb)
{
    uint8_t t;
    t =*pa;
    *pa =*pb;
    *pb =t;
} 

void HAL_CRC_MspInit(CRC_HandleTypeDef* crcHandle)
{

  if(crcHandle->Instance==CRC)
  {
  /* USER CODE BEGIN CRC_MspInit 0 */

  /* USER CODE END CRC_MspInit 0 */
    /* CRC clock enable */
    __HAL_RCC_CRC_CLK_ENABLE();
  /* USER CODE BEGIN CRC_MspInit 1 */

  /* USER CODE END CRC_MspInit 1 */
  }
}

void HAL_CRC_MspDeInit(CRC_HandleTypeDef* crcHandle)
{

  if(crcHandle->Instance==CRC)
  {
  /* USER CODE BEGIN CRC_MspDeInit 0 */

  /* USER CODE END CRC_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_CRC_CLK_DISABLE();
  /* USER CODE BEGIN CRC_MspDeInit 1 */

  /* USER CODE END CRC_MspDeInit 1 */
  }
}